Sound-regenerating machine.



wIvI. C. HOPKINS.

SOUND IIIiGENEN/IIING MACHINE. AFPLICTIO FILED 'DEC.24.`l9l3-YRENEWEDMAR. 22.11918.

1 ,27 1,528., y Patented July 2, 1918;

s sIIIETs-SIIEEI I.

Arm/SINUS f M. C. HUPKINS.

SOUND REGENERATINGMACHINE.

APPLICATION FILED 050.211,1913. IIENEwgn MAR. 22. 191s.

II.2?L528 Pawnee@ my 2,1918, v 3 SHEETS-SHEET 2.

BQ i l /ll IIII IVI. C. HOPKINS.

. SOUND REGENE-RATVJNG MACHINE.'- APPLxcATloN FILED m0251913. RENEwEDMAR.22.191

3 SHEETS-SHEET 3.

A TTOHIVEYS raras rama onirica.

MARCUS C. HOIKINS, OF NEW YORK, N. Y., ASSIGNOR, BY MESNE ASSIGNMENTS,TO

'LEKTOPHONE CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE.

Specifeatoii of Letters Patent.

Patented July 2, 1918.

Application filed December 24, 1913, Serial No. A808,577. Renewed March22, 1918. Serial No.. 224,()49

To all whom. zt may concern vBe it know'n that 1 MARCUsC. HOPKINS,

-a citizen'of the/United States, residing` in the borough of Manhattan,city, county, and State of New York, 'have invented cer* tain vnew anduseful improvements in Souncl-Regeneratingl kM'achines; and 1I do herebydeclare the following to be awfull,

' clear, and exact'des'cription of the invention,

such as will enable othersskilled in the art to vwhich it. app'ertainsto makeI and use the same.` y relates to improvements inA soundYregenerating vmachines.-

My invent-ion It relatesgy'particularly to sound regenerating machinesof the direct type in which thev sound Waves are regenerated by atympanum without 'the employment of amplification devices, such as hornsor trumpets.

My present invention is an improvement on the invention described andillustrated in an application filed by me July 14,1913, and havingSerialNumber 778.826.

The object of my present invention, is to provide a simple, etci'ent,and easily oper# ated mechanism, theI parts 'of which may be cheaplymade and assembled.'

A further object of my invention is to provide a mechanism in whichthef'style exerts a relatively powerful leverage in vibrating thetympanun'x, thereby greatly reducing the wear" on the record, and, byreason of the small relative* movement4 oi" the tympanum,eliniinating#distortions which would result from movements of greateramplitude; the tympanum being, however, ot' sucharea that the relativelysmall range ofmoveme'nt produces sound waves of large volume andcarrying power constituting, without ampliication by a sound box, hornor the like`r a substantial regeneration of the original recorded soundwaves.

of fFig. 3.

- bar and parts connected therewith, taken on the line 3 3 of Fig. 5. y

Fig. t is a Across sectionl on the line 4 4 Fig, 5 is'an end view ofwhat is shown in Fig. 3, looking at the end having the style holder. j A

Fig.` 6 is a longitudinal-vertical sectional view, a portion of thetransmissionl member and rigid bar being broken away, taken on the line(S-GofFig. 5.

Fig. 7 is-...a horizontal sectionalk51'view through the rigid bar,showing a modification, some of the parts being broken away;

Figs. S andi) are rspecti'velyside and end views of collars 17 and 19,the former being shown partially in section.

Similar reference characters designate similar parts in the differentviews.

1 designates the cabinet in which is mounted a suitable motor, notshown, which is adapted to drive a iat top revoluble record table 2,upon which is adapted to be placed a diskrecord 3. i

The cabinet at one end is providedr with a raised portiont whichprovides acompartmenty in which 'is disposed 'vertically a tympanum 5,preferably provided with a central conical portion G, to the apex ofwhich is secured a cap 7, to which is connected the transmissionmechanism, which will be hereinafter described.

'l he outer edges of the tympanum 5 are clamped between two ring members8 and 9, the latter being supported by radial rods l0, the inner ends ofwhich are tast-,oneri to a.4 collar 11, which is secured by a set. screw12, Fig. l. to a rigid horizontal cylindrical bar 13. which is supportedby a universal joint upon 'a bracket 14e, which is secured to a portionof the cabinet frame.

The universal joint just referred to comprises a ring' member 15, whichis pivoted by'means ot' two oppositely disposed trun nion screws 16 to acollar 17 in which the bar 13 is rotatable on its axis. i

Forlimiting the rotation of the bar 18, it

'has secured to it at one end of the collar 17,

a collar 19, shown in Fig. 9, which is provided With two notches 19, inthe end adjacent to the collar 17, said notches being adapted to receivea bolt 18 mounted in aA hole in the adjacent end of the collar 17,

yand normally forced outwardly by a` spring 18 contained in said hole,see Fig. 8.

The ring member at its lower side .is provided with a vertical stem 20pivoted 1n a socket in the bracket 14.

Vhen vthe bar 13 is rotated 'on its axis,

the bolt 18, by means of its pressure will retain the bar'in theposition to which it is rotated. The notches19 have inclined bottoms andat one set of ends terminate abruptly, whereby the bolt will readilyenter the notches, and -will readily vmove from :one

notch toward theother, but the abrupt ends of the notches will limit therotation ofthe bar in each direction.

Insulation 21 of suitable material, suchas soft rubber, may be providedbetween the bracket 1 4 and the part-.of the cabinet frame to which itis secured. i'

To enable the tympanum 5 to freely vibrate in unconfined air, and tovprovide paths to the surrounding atmosphere, the walls of the upstandingportion 4 of the cabinet may be provided with. asutlicient nu'inber ofopenings, and if desired, for protecting the closing the forward end ofthe portion 4 and for covering the record table 2.

j I will nowgdescribe the tensioned transmission mechanism.

Referring particularly. to Figs. 4 to 6, it will be noted that' the bar13 is provided therethrough with :L longitudinal hole 24,

4through which extends a transmission member comprising, preferably, alight rod 25,

` which extends through a notch in-a vertical lever 26, which isvpivoted on two 'fulcra 27 mountedin the bar 13, at -the adjacent endthereof,-and having'knife edges resting in recesses provided in thelever26. This lever carries a style 4holder 28 having a set screw 29 forsecuring thereto, at an inclination to w the axis ofthe lever 26, astyle 30. It will be notedl that the axis of the lever which carriesthe'style'holder 28.is disposed substantially perpendicular to therecord, when the style 30 is in the operativev position on the record.This disposition of the axis permits'the style to travel transverselyrelative to the surface of the record, and effects a more accurate'following of the undulations at thesides of the recordgroove than couldbe otherwise'obtained.l

. Th end of the rod 25, on the outer side of the lever 26 bears againsta member 31, to which it is secured by means of a. screw 32, whichextends through a' hole'p'rovided in the member 31.- The latter memberis provided on its innerside with knife edgesl the other side of theaxis of'said' lever, is a fiat spring 34, which is providedwith a holethrough which extends a screw 35, which isfmounted'in ascrewfthreadedhole in the adjacent `end of the bar'13, and'which has mounted upon it,preferably, twonuts 35v which bear respectively against fthe spring 34and the bar 13, and which serve to tightly clamp the 'screw 35 to thespring 34 and to 7`5 The transmission member 25` extends through a notchin the lever 38, and is secured tightly to the inner side of a member 40by-means of a connecting member'42,

which extends through the `member A40, 'against the outer side of whichit bears, and 1s provided with a threaded end whichis fitted in athreaded hole in the adjacent' end o f the member 25.

VThe member 40` is' provided with knife edges 4l which are'mountedinrecessesprovided thereforin the adjacent side of the lever 38. V

The other end of the connecting member 42 bears against'the inner sideof the cap7,

to which it is secured by a screw 43, which extends through a centralhole provided in the cap 7, -and fits in 'avthreaded hole in member 42.-l'

The cap 7 is provided with an` externally screw threaded central tubularprojection 'on which is 4fitted a clamping member'44, be` tween whichandthe cap 7 the tympanum 5 is clamped.

The screws 35 and hold the levers i and 38 against the'adjacent knifeedges', and- .also, by swinging the similar ends of the levers inopposite directions, impart a tenislon to the transmisslon member 25 in'the direction of its vibratory movement. YAs vthe spr1ngs-34 and 37counterbalance each other, the levers 26 and 38 are' free'tobe joscillated on their'supporting knife edges. in a plane, instead ofswinging in a, curve It will be noted that the tympanum sup-` portingrings 8 and 9. are mounted ",very..

closely tofthe universal joint on whichfthe. vbar 13 swings. Thispermits thestylefinV traversing the record, te .swing the tympa num andits support as on a pivot, andwithout unduewearl on the record, thestyle belng .located far from and the tympanumsup port near tothepivotal support of. the bar1'3.

` It will also be notedl that the dist-ance' of l the style 30 from'theaxis of the lever 26 is.

much greater' than the distance between the l axis andthe knife edgebearings 33515411@ member 31, to which the transmission member 25 issecured. By means ofthis construction, the length of vibration of thetympa- `num is much less than that of the style and the tympanum thusoffers little resistance to the movement of the style, thus greatlyreducing thewear of the record.' To compen-l sate vfor the smallmovement of the tympanu-m, it has a large areapreferably exceeding'nineinchesrin diameter', and is, preferably, provided centrally with a rigidportion of relatively large area, whereby it is enabled to move a largebody of air, so as to to the Arapid mechanical vibrations of the.

style holder, and suchgmoleeular vibrations as are transmitted to it,vrare transmitted to tained by employing a tympanum, having an While thelevers26 and 38 and the rod 25 are under tension.` this tension is notex.-

the tympanum Without distortion.

tended tothe tympanum, but the tympanum, preferably, is left untensionedso as to freely move. The tympanum, being conical, will be very rigid`and will, therefore, be Amoved bodily, instead of having merely a localdisturbance set uptherein, as would be the case if it were fiat and of ayielding nature.

In the operation of' the invention, the bar 13, which serves as ahandle, and for which purpose it is provided at its forward end with acap 45,'having a lateral finger piece 46, Fig. 1,A is swung on theuniversal joint to the proper position for playing. The bar may berotated on its axis, by grasping the finger piece 46, to a position inwhich a style may be removed from or inserted into the style holder 28.The cap 45 is provided at its forward end with a hole through which thestyle holder 28 projects.

In 'the form of my invention shown in Fig. 7, the construction is thesame as that shown in Figs. 4 to 6, excepting that for the springs 34and 37, which swing the levers 26 and 38, there is provided a springWire 47, which extends through the hole 24 in the bar 13, and which hasits ends secured by screws 50 toknife. edge members 49, which bearsrespectivelyupon the outer sides of the levers 26 and 38,fwhichcorrespond in function and location to the levers 26 and 38 of the otherform of my invention. The levers 26/ and 3S are mounted. respectivelyupon knife edge bearings 27 and 39, which are secured in opposite endsof the bar 13.

vAs in the other form of my invention, the

transmission member -25 is connected by a connecting member 42 tothetympanum, and has a longitudinal tension imparted toit by the levers26 and 38"` through the intermediacy of the spring wire 47 which isprovided with a-convolution 48, which permits the wire 47 to exert aspring tension.

In the form of my invention shown in Fig. 7, lthe springwire 47 alsoholds' the leversfirmly seated upon their fulcra.

1 When lthefstylus 30 is swung by. the record, its vibrations will betransmitted mechanically by the leversQG and 38', the wire 47, rod 25and connecting member '42, to the cap 7, and from the cap to thetympanum.

Vhile, for convenience of illustration, I have shown the relativedistances between the axis and stylus, and between the axis and theknife edges supporting the transmission member 25, as being 'about threeto one, it is desirable that this proportion should be largelyincreased, and that the transmission member 25 should be connected tothe levers 26 and 3S very close to their axesfk I vhave found that, indirect sound regeneration from a record, the very best .results areobarea sufficient to movea large amount of air,

'ISO as to producel the desired volume and carbe longitudinally veryrigid and at the same time easily oscillated. These conditions arerealized. in the structure of .this invention, the direct connection ofthe tympanum with the tensioned transmission member, and the springpressed levers effecting the longitudinal rigidity; and the employmentof knife edge bearings for the joints effecting the required freedom ofoscillation. tioning of the knife. edge supports for the tensionedtransmission member very close to the axis of the style holder relativeto the much greater distance between said axis and the point of thestyle, eii'ects the desired leverage for the style upon the tv vmpanuniand imparts to the tympanum the ver)v slight movementdesired, the.limited movement of `the tympanum being coi-npe-nsated for by itsI Theposimuch less movement of the tympanum, mustI l the groove of a recordtablet are transmitted transmission member carried by said levers,

a style holder carried by one of said levers,

a tympanum connected to said transmission member, and t'wo springsrespectively operating upon said levers to yeffect a tension in saidtransmission member.

3. In a sound regenerating machine, a"

rigid support carrying two knife edges, a vibration transmission member,two levers carrying said member and respectively pivoted on said knifeedges, a style holder carried by one of said levers, a tympaiiumconnected with said transmission member, and yielding means operatingvupon said levers to effect a tension insaid transmission inember and toretain said levers-seated on said knife edges. f

4; In a sound regenerating machine, a

rigid support, two levers pivoted thereon, a.

transmission member carried by said levers, a style holder carried byone of said levers,

' a tympanum connected to said transmission member, two springs securedrespectively to said levers, and means, operating upon said springs forforcing said-levers to positions in which a tension will be imparted tosaidV transmission member. v

5. In a sound regenerating machine, a bar having fulcra at'its oppositeends, two levers respectively pivotedon said .fulcra, a style holdercarried 'by one lever, a' transmission member carried by said levers, atympanum connected with said transmission'. member,

' and two springs respectively operating'upon said levers to im-part atension to said transmission member.

6. In a sound regenerating machine, a bar,

' two levers pivoted thereto at opposite ends thereof, a style holdercarried by one of said levers, a transmission member carried by saidlevers, a tympanum .connected with saidtransmission member, two springsrespectively carried by saidv levers, and means car'- ried by -said barand yoperating upon said springs to force said levers to positions inwhich a 'tension will be imparted to 'said f ,transmission member.

7. In a sound regenerating machine, a bar` having a longitudinal holetherethroughand provided at opposite ends with fulcra, two

levers respectively pivoted on said fulcra,a style holder carried by oneof said levers, a

transmission member extending through said hole and carried by saidlevers, a tympanum connected with said transmission ni'ember,v'and"'f'yielding tensioning means operating upon said levers forimparting a continuous lengthwise tension to said transmission member. y

8. In a. sound 'regenerating machine, a bar having a hole longitudinallytherethrough, two levers pivoted to opposite ends: thereof, astyleholder -carriedby' one of;

said levers, a transmission niember'carried.

by said levers and extending through said hole, a tympanum connectedwith said transmission member, and resilient means operatingv upon saidlevers for effecting aiension in said transmission member.

9. In a sound fregenerating machine, a

bar having -a .longitudinal hole therethrough, two levers pivoted toopposite.

ends thereof, a-style holder carried by one of said levers,atransmission meinber'cai'fried by said levers and extending throughsaid hole, a tympanum connected with said transmission member, twosprings carried' respectively by said levers, and means by which saidsprings operate on said levers to limpartl member.

a tension to v'said transmission'.

10. In a sound regenerating machine, a

vibration transmission' support, a style holder and a tympanum supportcarried thereby, and means for `pivotally supporting said transmissionsupport at a' point closely adjacentto said tympanum support and remotefrom said style holder, Said means providing for the rotation of. saidtransmission support upon its longitudinal axis. y

11. In a sound regenerating machine, a

vibration transmission support, style holder and a tympanum supportcarriedl therebyfand a universal bearingpivotally supporting saidtransmissionsupport at a point closely adjacent to said tympanumsupportan relativelyA remotev from ,said

style holder, said bearing` providing for the rotation of saidtransmission support upon its longitudinal axis.

'12. In a-sound regenerating machine, a vibration transmission support,av lstyle holder and a tyinpanum support carried thereby, and a bearingpivotally supporting said transmission support at a point closelyadjacent to said .tympanum support and relatively remote. from' saidstyle holder,

said bearing comprising two pivoted members, one pivoted on the other,the transmission support beingrotatable about its longitudinal axis onone of said members, v'the axes of said members being at right anglestoeach other..

13. In a machine for directly regenerat- I ing sound from a record ofythe same,- a vibratile conical tympanum of large area rigidly supportedat its periphery and freely exposed to .unconned air, a stylus-holder, avibration' transmission member connected to the tympanum, and a pivotedvlever con'-4 sion member; the-connection of said lever with thetransmission member being considerably closer to the pivot than' is therecordengaging end ofa stylus Asupported in the holder, whereby vthe`movements of the tympanum are of substantially less4 amplitude than themovements of the record-engaging end of the stylus, the tympanum beingof sufficient area to impart to the surrounding free air, when thetympanum is so vibrated, sound waves substantially corresponding inintensity to the recorded sound waves.

14. Ina machine for directly regenerating sound from a record of thesame, a vibratile conical tympanum of large area rigidly supported atits periphery and freely exposed to unconfined air, a stylus-holdenavibration transmission member connected to the tympanum, means fortensioning the transmission member independent of the tympanum in thedirection of itsvibration, anda pivoted lever connecting the stylusholder with the transmission member, the connection of the lever withthe transmission member being considerably closer to thepivot than isthe record-engaging end of a stylus supported in the holder, Whereby themovements of the tympanum are of substantially less amplitude than themovements of the record-engaging end of the stylus, the tympanum beingof suiiicient area to impart to the surrounding free air, when thetympanum lis so vibrated, sound waves substantially corresponding inintensity'to the recorded sound Waves.

15. In a sound regenerating machine, a style, a tympanum oflarge arearigidly supported at its periphery and freely exposed to unconned air,and transmission means tensioned, independently of the tympanum, in thedirection of its Vibration and connecting the style and tympanum andartions Which are relatively much Vshorter than the vibrations of therecord end of thev style, the tympanum having a vibratile areasufficiently large to effect, without amplification, sound waves oflarge volume and carrying power.

16. In a sound regenerating machine, a support, two oscillatablemembers, knife edge bearings on said support respectively "supportingsaid members, knife edge bearings mounted respectively on said members,a transmission member mounted on the last named bearings and adapted tobe actuated by a style, a tympanum connected with said transmissionmember, andmeans for holding said oscillatable and transmission memberstightly against the bearings which respectively support them.

17. In a sound regenerating machine, a support, tWo oscillatablemembers, knife edge bearings mounted on said support and f respectivelysupporting said` members, a tensioned transmission member adapted to bevibrated by a style, and knife edge bearings respectivelymounted on saidoscillatable members and supporting said transmission member.

18. In a machine for directly regenerating sound, a vibratile conicaltympanum of large area rigidly supported at its periphi ery and freelyexposed to unconiined air, a

sound-vibrated element, and a single transmlsslon member between saidtympanum and said element maintained under tension' land arranged toimpart to the tympanum vibrations which are relatively much shortervthan the lvibrations imparted to said element.

In test1mony whereof I aiiix my signature, 1n presence of two witnesses.

MARCUS c. HoPKiNs. Witnesses R. S. SCHLFF, M. A. BILL.

